Installed a new digitizer and everything tested fine. During final assembly, backlight connector came off daughter board. Didn't realize this until it booted up. Thought a backlight chip maybe had been fried. Relieved to see that it was just a connector. After powering off and rechecking all connections. Started the unit up and now zero touch. Solder job was perfect. At a loss as to what the issue is now. Very little information out there on this.